Re: [MirageOS-devel] Camlp4 Stack_overflow

[Thomas Gazagnaire <thomas@xxxxxxxxxxxxxx>]

do you have an example of what the generated source file looks like ? 

Would be interesting to report the bug upstream: 
https://github.com/ocaml/camlp4/issues

Thomas

On 7 May 2014, at 23:38, Anil Madhavapeddy <anil@xxxxxxxxxx> wrote:

> To address the camlp4 problem, you can use the _tags file to mark just
> the one source file as not passing through camlp4 (via a '-' somewhere
> to remove the tag -- will need to look up the details in the manual).
> 
> The easiest way to solve your problem would be just to have a crunched
> file containing the information in CSV or S-expression format, and then
> reading from it at application startup time to initialize your array.
> 
> The 'crunch' mode would compile all this into a standalone kernel, or
> in Unix mode would be a filesystem passthrough for easier development.
> Any reason you want it to be a 'hand written' OCaml file?
> 
> -anil
> 
> On 7 May 2014, at 14:06, André Næss <andre.naess@xxxxxxxxx> wrote:
> 
>> I've rewritten the generated code so that it creates an array and then
>> assigns to indexes of the array, batching the assignments using
>> multiple let () =
>> 
>> Compilation speed is a problem, and it still falls over at 50K entries.
>> 
>> I suppose I could somehow write the data to an image and read it back
>> in at application startup, but I think I actually like my current
>> approach. All of the work is done at compilation time. The rows are
>> written in sorted order so a simple binary search can be used. The
>> resulting application is entirely single-purposed.
>> 
>> Any ideas for other ways to do this? Bypass the compiler and "compile"
>> the data myself? Does there exist tools to do something like that?
>> 
>> On Wed, May 7, 2014 at 1:40 PM, André Næss <andre.naess@xxxxxxxxx> wrote:
>>> Hi
>>> 
>>> I'm trying something that might be a bit silly but it's just intended
>>> as an internal demo of Mirage to my team. I'm writing a tiny HTTP
>>> based application whose only purpose is to allow you to search a phone
>>> book.
>>> 
>>> I've based my approach on the approach you've used for static websites
>>> using crunch where you compile the web pages into the executable. In
>>> my case that means I take the list of name and number pairs and stuff
>>> them into an array. So part of my config.ml file emits a single Pb.ml
>>> file which contains an array declaration like this:
>>> 
>>> let db = [|("Aaron Jaksic",1571268);
>>> ("Aaron Mcdivitt",1454629);
>>> ("Aaron Reuben",1765247);
>>> ("Aaron Sardinha",1224806);
>>> ("Abbey Gowens",1267083);
>>> ("Abbey Hathcox",1309490);
>>> ...
>>> 
>>> As the title say I'm running into problems compiling this when I
>>> create a large phone book, the error being:
>>> 
>>> Camlp4: Uncaught exception: Stack_overflow
>>> 
>>> This happens with 25K entries, it works with 10K entries.
>>> 
>>> Is there some way I can prevent Camlp4 from being run on the Pb.ml
>>> file? Or will I just have to generate a file that builds the array at
>>> runtime somehow?
>>> 
>>> André
>> 
>> _______________________________________________
>> MirageOS-devel mailing list
>> MirageOS-devel@xxxxxxxxxxxxxxxxxxxx
>> http://lists.xenproject.org/cgi-bin/mailman/listinfo/mirageos-devel
> 
> 
> _______________________________________________
> MirageOS-devel mailing list
> MirageOS-devel@xxxxxxxxxxxxxxxxxxxx
> http://lists.xenproject.org/cgi-bin/mailman/listinfo/mirageos-devel


_______________________________________________
MirageOS-devel mailing list
MirageOS-devel@xxxxxxxxxxxxxxxxxxxx
http://lists.xenproject.org/cgi-bin/mailman/listinfo/mirageos-devel